2019-09-15T08:42:30ZSIMULTANEOUS FITS IN ISIS ON THE EXAMPLE OF GRO J1008–57http://hdl.handle.net/10467/67192
SIMULTANEOUS FITS IN ISIS ON THE EXAMPLE OF GRO J1008–57
Kühnel , M.; Müller , S.; Kreykenbohm , I. Kreykenbohm; Schwarm , F.-W.; Grossberger , C.; Dauser , B. T.; Nowak , M. A.; Pottschmidt , K.; Ferrigno , C.; Rothschild , R. E.; Klochkov , D.; Staubert , R.; Wilms , J.
Parallel computing and steadily increasing computation speed have led to a new tool for analyzing multiple datasets and datatypes: fitting several datasets simultaneously. With this technique, physically connected parameters of individual data can be treated as a single parameter by implementing this connection directly into the fit. We discuss the terminology, implementation, and possible issues of simultaneous fits based on the Interactive Spectral Interpretation System (ISIS) X-ray data analysis tool. While all data modeling tools in X-ray astronomy in principle allow data to be fitted individually from multiple data sets, the syntax used in these tools is not often well suited for this task. Applying simultaneous fits to the transient X-ray binary GRO J1008–57, we find that the spectral shape is only dependent on X-ray flux. We determine time independent parameters e.g., the folding energy Efold, with unprecedented precision.
2015-01-01T00:00:00ZPROTECTION OF WOODEN MATERIALS AGAINST BIOLOGICAL ATTACK BY USING NANOTECHNOLOGYhttp://hdl.handle.net/10467/67191
PROTECTION OF WOODEN MATERIALS AGAINST BIOLOGICAL ATTACK BY USING NANOTECHNOLOGY
Havrlik , Michal; Ryparová , Pavla
This article is focused on protection of wooden materials by using nanofibrous textiles with biocidal addition, which continues on the work of a group at the Center for Nanotechnology at the Faculty of Civil Engineering in the CTU. Timber is a natural material which is predisposed for biodegradation and therefore it is essential to study suitable and effective protection against microorganisms. Wood is a material susceptible to biological corrosion and therefore it is necessary to protect it. The study compares biocidal efficiency of polymer solution as a coating and as a layer from nanofiber textiles. We used polyvinyl alcohol (PVA) as a basic polymer which was enriched by substances from commercial Lignofix E – profi, solution of CuSO4 · 5H2O and AgNO3 and finally colloidal silver as an example of nanoparticles. The final concentration of the biocidal substance was 1 (v/wt)% in fiber. The nanofiber textiles are produced on the device Nanospider NS LAB 500 (Elmarco, CR) on cylinder rotating electrode. The study was divided into two parts, the first being an agar plate test and the second a test on samples from timber. The mixture of mold was used as the model organism. (Alternaria tenuissima, Pochonia bulbiosa, Trichoderma viride and Acremonium sclerotigenum). Comparison of efficiency between the polymer paint and nanofiber textiles showed no difference. The best results were shown by PVA with an addition of substances from the commercial biocidal treatment Lignofix-E Profi on the agar plate. The difference of result was shown on timbre samples, finding that the best results were with treatment by PVA doped by Silver nitrate. The anticipated results were shown by treatment with non-doped PVA, which does not have any fungicidal protective effect.
2015-01-01T00:00:00ZMECHANICAL DISINTEGRATION OF WHEAT STRAW BY ROLLERPLATE GRIND SYSTEM WITH SHARPEDGED SEGMENTShttp://hdl.handle.net/10467/67190
MECHANICAL DISINTEGRATION OF WHEAT STRAW BY ROLLERPLATE GRIND SYSTEM WITH SHARPEDGED SEGMENTS
Kratky , Lukas; Jirout , Tomáš
Colloid mills and extruders are widely used for disintegrating wet fibrous biomass. However, their main disadvantages are a high energy requirement in the range of hundreds or thousands of kWh per ton of material, and the fact that they grind in process cycles. Efforts have therefore been made to design a new type of continuously operated grinder. Its disintegration principle uses a roller-plate grinding system with sharp-edged segments, where the compressive and shear forces combine to comminute the particles. Test experiments verified that the grinder disintegrates wet untreated straw to particles below 10mm in an effective manner in a single pass, with an energy requirement of 50 kWht−1 TS. A 23% increase in biogas yield was achieved, leading to a net gain in electric energy of310 kWht−1 TS.
2015-01-01T00:00:00ZIMMOBILISATION OF HUMIC SUBSTANCES USING PLASMA MODIFICATIONhttp://hdl.handle.net/10467/67189
IMMOBILISATION OF HUMIC SUBSTANCES USING PLASMA MODIFICATION
Hájková , Pavlína; Tichý , David; Čmelík , Jiří; Antoš , Petr
This paper presents a study of the immobilization of humic substances (HSs) on a polypropylene (PP) nonwoven fabric. In order to attach the HSs, the PP nonwoven fabric was modified in a volume of nonthermal atmospheric pressure dielectric barrier discharge (DBD) under defined conditions. An unmodified PP nonwoven fabric was used as a reference sample. The modified and unmodified samples were both dipped in an aqueous solution of potassium humate, and then the samples were washed in water and the amount of HSs attached to the PP fabric was monitored. An aqueous solution of cadmium salts was filtered through the treated fabric, the content of Cd2+ in the solution was monitored using ICP-OES analysis, and the Cd2+ sorbed on the fabric was proved by SEM/EDS analysis. The efficiency of the PP plasma modification was proved by XPS analysis, and the presence and the distribution of the HSs along the fibers was proved by SEM analysis.
2015-01-01T00:00:00Z